{"id":"CVE-2026-72142","state":"PUBLISHED","title":"i2c: imx: fix locked bus on SMBus block-read of 0 (atomic)","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: imx: fix locked bus on SMBus block-read of 0 (atomic)\n\nSMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the atomic\n(polling) path rejects it as -EPROTO. Worse, it returns without a\nNACK+STOP: the next receive cycle has already started, so the target\nkeeps holding SDA and the bus stays stuck until a power cycle for\nthis i2c controller.\n\nReading I2DR to obtain the count likewise arms the next byte on the\ncount > I2C_SMBUS_BLOCK_MAX path, which also returned -EPROTO directly\nand left the bus held.\n\nHandle both: NACK the in-flight dummy byte (TXAK) and extend msgs->len so\nthe existing last-byte handling emits STOP; the dummy byte is discarded.\nA count of 0 is a valid empty block read; a count above\nI2C_SMBUS_BLOCK_MAX is still reported as -EPROTO, but only after the bus\nhas been released.\n\nThe interrupt-driven path has the same flaw from a later commit and is\nfixed separately, as it carries a different Fixes: tag and stable range.","publishedAt":"2026-08-15T05:53:15.489Z","updatedAt":"2026-08-23T12:46:51.665Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"0f29df3c3d607a9dbc14aed0e45504ced4d2e7ec","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"38d4947431b2410850409fda016b2ac9f640a4dd","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"e3e8b02d4773cfc5ad561d2e5505efde36c6927a","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"016ef0f6ca4bc9bf0330ac41bd2ea349759643e3","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"c882e8cc68fb993700dc21fd6e754001e6297934","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"6d2c973926d0612360693bc559be2ffde836151b","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"60ed00d46616a9232e42ea7a3e3c0273d7cf7543","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"cb2fc37857693b55909fb77dc2c87cfbc1cdc476","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/busses/i2c-imx.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.16","versionType":"semver"},{"version":"5.10.266","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.217","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.184","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/busses/i2c-imx.c"]}],"references":["https://git.kernel.org/stable/c/0f29df3c3d607a9dbc14aed0e45504ced4d2e7ec","https://git.kernel.org/stable/c/38d4947431b2410850409fda016b2ac9f640a4dd","https://git.kernel.org/stable/c/e3e8b02d4773cfc5ad561d2e5505efde36c6927a","https://git.kernel.org/stable/c/016ef0f6ca4bc9bf0330ac41bd2ea349759643e3","https://git.kernel.org/stable/c/c882e8cc68fb993700dc21fd6e754001e6297934","https://git.kernel.org/stable/c/6d2c973926d0612360693bc559be2ffde836151b","https://git.kernel.org/stable/c/60ed00d46616a9232e42ea7a3e3c0273d7cf7543","https://git.kernel.org/stable/c/cb2fc37857693b55909fb77dc2c87cfbc1cdc476"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72142.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72142","state":"PUBLISHED","datePublished":"2026-08-15T05:53:15.489Z","dateUpdated":"2026-08-23T12:46:51.665Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.908Z"},"containers":{"cna":{"title":"i2c: imx: fix locked bus on SMBus block-read of 0 (atomic)","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: imx: fix locked bus on SMBus block-read of 0 (atomic)\n\nSMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the atomic\n(polling) path rejects it as -EPROTO. Worse, it returns without a\nNACK+STOP: the next receive cycle has already started, so the target\nkeeps holding SDA and the bus stays stuck until a power cycle for\nthis i2c controller.\n\nReading I2DR to obtain the count likewise arms the next byte on the\ncount > I2C_SMBUS_BLOCK_MAX path, which also returned -EPROTO directly\nand left the bus held.\n\nHandle both: NACK the in-flight dummy byte (TXAK) and extend msgs->len so\nthe existing last-byte handling emits STOP; the dummy byte is discarded.\nA count of 0 is a valid empty block read; a count above\nI2C_SMBUS_BLOCK_MAX is still reported as -EPROTO, but only after the bus\nhas been released.\n\nThe interrupt-driven path has the same flaw from a later commit and is\nfixed separately, as it carries a different Fixes: tag and stable range."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"0f29df3c3d607a9dbc14aed0e45504ced4d2e7ec","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"38d4947431b2410850409fda016b2ac9f640a4dd","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"e3e8b02d4773cfc5ad561d2e5505efde36c6927a","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"016ef0f6ca4bc9bf0330ac41bd2ea349759643e3","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"c882e8cc68fb993700dc21fd6e754001e6297934","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"6d2c973926d0612360693bc559be2ffde836151b","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"60ed00d46616a9232e42ea7a3e3c0273d7cf7543","versionType":"git"},{"version":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a","status":"affected","lessThan":"cb2fc37857693b55909fb77dc2c87cfbc1cdc476","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/busses/i2c-imx.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.16","versionType":"semver"},{"version":"5.10.266","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.217","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.184","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/busses/i2c-imx.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/0f29df3c3d607a9dbc14aed0e45504ced4d2e7ec"},{"url":"https://git.kernel.org/stable/c/38d4947431b2410850409fda016b2ac9f640a4dd"},{"url":"https://git.kernel.org/stable/c/e3e8b02d4773cfc5ad561d2e5505efde36c6927a"},{"url":"https://git.kernel.org/stable/c/016ef0f6ca4bc9bf0330ac41bd2ea349759643e3"},{"url":"https://git.kernel.org/stable/c/c882e8cc68fb993700dc21fd6e754001e6297934"},{"url":"https://git.kernel.org/stable/c/6d2c973926d0612360693bc559be2ffde836151b"},{"url":"https://git.kernel.org/stable/c/60ed00d46616a9232e42ea7a3e3c0273d7cf7543"},{"url":"https://git.kernel.org/stable/c/cb2fc37857693b55909fb77dc2c87cfbc1cdc476"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-23T12:46:51.665Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"5.10.266"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"5.15.217"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.1.184"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}